Polyembryony, Biology

Assignment Help:

Polyembryony

Presence of more than one embryo in a seed is termed polyembryony. The phenomenon, first discovered in orange seeds by Leeuwenhoek (1719), attracted considerable attention because of its potential for application in and horticulture. Polyembryony is broadly classified into simple and multiple, depending on whether the supernumerary arises in one or more embryo sacs in the ovule. Simple polyembryony may be sexual or asexual. In sexual polyembryony embryos may originate from the fertilized egg and synergids, or by budding or cleavage of the polyembryony cells or suspensor of the zygotic embryo.

Asexual embryos are produced within the embryo sac without fertilization. Embryos may also originate from diploid nucellar or integumentary cells of the ode and grow into the embryo sac. These embryos are termed adventive or sporophytic. Multiple polyembryonies involve production of accessory embryos from two or more embryo sacs in the same ovule. For example, in the sea Island cotton, Gossypium barbadense, fertilization of egg in one embryo sac stimulates the induction of embryo from an unfertilized egg in the adjacent embryo sac within the same ovule. Thus, diploid-haploid twin embryos are produced in the seed.


Related Discussions:- Polyembryony

Explain high fibre diets, High fibre diets High fibre  diets: The pat...

High fibre diets High fibre  diets: The patients  are advised  to  eat  high  fibre cereals as whole grain flour and bread, whole grain bread cereals, whole wheat pasta and b

What does the formula dpd = sf - tp signify, Q. What does the formula DPD =...

Q. What does the formula DPD = SF - TP signify? DPD is the short form of diffusion pressure deficit, SF (suction force) is the vacuolar osmotic pressure and TP is the turgor pr

What is the physiological explanation for archaic method, In ancient Greece...

In ancient Greece the father of Medicine, Hypocrates, described a method of diagnosing diabetes mellitus by tasting the patient's urine. What is the physiological explanation for t

Drugs derived from plants, A large number of important drugs are derived fr...

A large number of important drugs are derived from plants. For example Tubocuranin, derived from plant-based curare, is used as a muscle relaxant during surgery. Curianol, a Guy

Define fluid and electrolytes requirements in elderly, Define Fluid and Ele...

Define Fluid and Electrolytes requirements in elderly? Care lo be taken that adequate fluid be given to the elderly. If patient is unable to take the required daily needs, then

What is enzyme assay, What is Enzyme assay Enzyme assay may also be use...

What is Enzyme assay Enzyme assay may also be used to determine whether stored plant products are suitable for use as food commodities, for e.g.  α-amylase should be present

Demographic cycle, DEMOGRAPHIC CYCLE - 1 .       First stage - B...

DEMOGRAPHIC CYCLE - 1 .       First stage - B high     - D high     =  0 2 .       Second stage - B high     - D lo w     =  G more eg.

Explain endoskeleton in detail, Explain Endoskeleton in detail. Support...

Explain Endoskeleton in detail. Supporting structures of the skeleton surrounded by the body tissues. As a consequence, there is living tissue on all sides of endoskeletal stru

What is the permeability to sodium ions, An impermeable membrane separates ...

An impermeable membrane separates a one liter solution of 1M NaCl in the left compartment from a one liter solution of 2M KCl in the right compartment.  At 2 AM the membrane became

Genetics, name a disorder of human blood that is caused by mutation

name a disorder of human blood that is caused by mutation

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd